What Are the UV Aging Test Standards?

General Standards

ASTM D 4459, ASTM G 154, ISO 4892, IEC 60068, ISO 4892-1, ASTM G151, ASTM G154, JISD0205, SAEJ2020

Plastics

ISO 4892-3, ANSI C57.12.28, ANSI A14.5, ASTM D4329, ASTM D4674, ASTM D5208, ASTM D6662, DIN 53384, UI K 3750, UNE 35 104

Coatings

ASTM D3794, ASTM D4587, FED-STD-141B, GM 9125P, JIS K 5600-7-8, ISO 11507, ISO 20340, M598-1990, NACE TM-01-84, NISSAN M0007, PrEN 927-6

Textiles

AATCC TM 186, ACFFA GUIDELINE

Roofing Materials

ANSI/RMA IPR-1-1990, ASTM D4799, ASTM D4811, ASTM D3105, ASTM D4434, BS D5019, BS 903: PART A54, CGSB-37.54-M, DIN EN 534

Printing Inks/Art Materials

ASTM D3424, ASTM F 1945

4. Which Instrument Brand Is Recommended for UV Testing?

The UV ultraviolet aging tester is the most widely used UV aging testing machine globally. It provides reproducible and reliable aging test data in just a few weeks or months. Its short-wavelength UV light and condensation cycles realistically simulate the damaging effects of sunlight, dew, and rain on materials.

5. Common Misunderstandings About UV Testing

How Many Outdoor Days Does 1 Day of UV Testing Equate To? How Many Years Does 2000 Hours of UV Testing Equate To?

Theoretically, it is impossible to calculate outdoor exposure time by multiplying the hours in an aging tester with a single conversion factor. The issue is not the lack of precise aging testers; even with the most sophisticated or expensive equipment, such a "magic coefficient" remains elusive. The primary challenge lies in the inherent variability and complexity of outdoor environments. The relationship between tester exposure and outdoor exposure is influenced by numerous variables, including:

• Geographic latitude of the exposure site (closer to the equator means stronger UV radiation)
• Altitude (higher altitudes mean stronger UV radiation)
• Local geographical features (e.g., wind drying samples, proximity to water bodies facilitating dew formation)
• Year-to-year weather variations (leading to differences in aging effects at the same location)
• Seasonal changes (e.g., winter exposure may be only 1/7th of summer exposure)
• Sample orientation (5° south-facing or vertical north-facing)
• Sample insulation (back-plated outdoor samples often age 50% faster)
• Tester operating cycles (hours of light and moisture)
• Tester temperature (higher temperatures accelerate aging)
• Material properties and spectral power distribution (SPD) of the light source

Logically, discussing conversion factors between accelerated aging hours and outdoor exposure months is meaningless. One condition is constant, while the other varies. Seeking such a factor often exceeds the scope of valid data. Aging data is relative.

Nevertheless, valuable weather resistance data can still be obtained from accelerated aging testers. However, it is essential to recognize that this data is relative, not absolute. What you can reliably gain from laboratory tests is a material's weather resistance rating compared to others.

The same applies to Florida exposure tests. Comparing 1 year of outdoor south-facing 5° "black box" exposure to 1 year of indoor or in-car exposure is impossible. Even outdoor tests only provide information on relative service life.